How do I change RGB value without changing the Alpha channel?

Question

I would like to know how can I change color of RGBA image when alpha channel will be unchanged for each pixel. If I use Paint Box Tool it will set alpha channel for all pixels to constant value.

Look at picture:

Answer 1

There's an option somewhere on the tools pallet called 'preserve transparency' that should do exactly what you are looking for.

Answer 2

The fast way to accomplish this, rather than using the Paint Bucket, is to use the keyboard shortcuts.

To fill with color while preserving transparency hold down Shift while you fill using:

• Ctrl-Backspace/⌘-Delete or
• Alt-Backspace/Option-Delete

I don't remember when I last used the Paint Bucket. It's been so long I'd forgotten it was there...

Answer 3

Although not as slick as Alan's method, which I will be using after this, a general method is to lock layer transparency before fill, painting, filters, etc.

Answer 4

All the current answers are probably better solutions in most cases, but in some cases you can also:

• Just apply a layer style to the color/gradient/pattern you want. Which I find slightly easier to make adjustments to—since you can adjust the color using the color picker dialog with a live preview, and layer styles also have other advantages (being saveable, easily transferred/copied, gradients hold up better when converting color profiles)

• Using a clipping/layer mask—this can be done in a few ways:

  1. Load the selection from the existing layer; then create a new fill layer (either a solid color, gradient or pattern).
  2. Or select the existing layer and hit Ctrl+Shift+N to create a new layer, checking the Use Previous Layer to Create Clipping Mask option.
  3. Or just select the existing layer; hit Ctrl+Alt+Shift+N, and then hit Alt+Ctrl+G
  4. Or you can create a layer mask by loading selection from the existing layer and then going to Layer > Layer Mask > Reveal Selection.

  It's a slightly more roundabout way to achieve the same general thing, but clipping/layer masks let you do some cool things sometimes, like just painting or pasting images into the layer and still preserve the alpha channel.